The Electro Sapper, or simply Sapper (Mentioned by the Sentry Operational Guide as FM/AM Ultra-Sapper), is used by the Spy to destroy an Engineer's buildings. The Spy selects the weapon, stands near an enemy structure, and uses the primary fire button to place a charge. Prior to placement, a white sapper outline appears on the structure, indicating that the building is in range to be sapped. Once the charge is placed, life will slowly drain from the building until it is destroyed. A sapped building will cease to function (sentry guns will not fire, dispensers will not heal or dispense ammo, teleporters will not spin). When a sapper is attached to one end of a teleporter, another sapper is automatically placed on the other end of the teleporter, if it exists.

An Engineer can remove the charge with two hits from his Wrench, if an Engineer removes a Sapper from a teleporter, the Sapper at the other end is also removed. If another Engineer strikes the Sapper first, he can get an assist for the Sapper kill, and a Medic healing an Engineer can also score an assist in this way. Pyros equipped with the Homewrecker can also destroy Sappers in one hit if they happen upon them, but this happens less frequently, as Pyros receive no alerts regarding friendly buildings (Engineers can also get assists from Pyros in the same way they can from other Engineers).

A small gauge is visible on the Electro Sapper when it is being carried. It serves no purpose other than for aesthetics, although the "meter" will rise if a Spy highlights a building to be sapped. The sapper has infinite ammunition and no discernible "cooldown" time. It is possible to repeatedly place Sappers on a building faster than an Engineer can remove them, but this tactic seldom works if there are other enemies around.

Note that while you may hear a "clamp" sound when you deploy a sapper onto enemy equipment, this sound is not heard by other players. They do, however, see the sapper device, the sparks, and hear a hissing noise. The Engineer who owns the structures will receive a warning in his HUD and will be aware that a Spy is near his equipment. The Engineer also says a line of dialog that can be heard by himself and players near him: "Spy's sappin' mah sentry!" for a sentry gun, as an example. Also, when disguised, if you attach a sapper, your disguise slaps down his right hand in front of him (an animation unique to disguised Spies), which is visible to enemy players.

A destroyed Sapper, by the "Destroy 3 0" command, only drops metal if it was attached to a dispenser, otherwise no metal is dropped. This method drops 9 metal, 3 for each piece of the sapper.

Damage

The Sapper deals 25 damage to buildings per second.

Destroys:

Level 1 Building (150 health) in 6.00 seconds

Level 2 Building (180 health) in 7.20 seconds

Level 3 Building (216 health) in 8.64 seconds

Weapon Demonstration

Previous Changes

Previously, it was possible to inflate your score by using the "destroy 3 0" command to repeatedly place and destroy electro-Sappers, as each new Electro Sapper would give you a point. This has since been fixed as of the December 2, 2010 Patch

Bugs

When the Electro Sapper is held with a left-handed view model, the text on the front of the Electro Sapper will be displayed backwards.

The view model for the Electro Sapper depicts the Spy holding it with his right hand, yet the world model has him holding it with both hands.

The view model for the Electro Sapper appears to only have one connector cable attached to it, yet when it is placed on a building, two appear to be attached.

Note: Any weapon except a wrench will decrease the amount of time needed to sap a building by reducing its health. This applies even to classes that aren't normally focused on destroying buildings.

Trivia

When the Sapper is held with a left-handed view model, the text on the front of the sapper will be displayed backwards.

The view model for the Sapper depicts the Spy holding it with his right hand, yet the world model has him holding it with both hands.

In the TF2 "Sentry Operation Manual" the Sapper is named as the "FM/AM Ultra-Sapper".

The Electro-sapper can be destroyed, much like an Engineer's building, by binding a button to destroy 3 0. If destroyed whilst on a dispenser, it drops 3 pieces for 3 metal each. This can be used to refill cloak.

Although it was sped up severely, the Spy would slowly flick a switch on the Sapper's interface. This did not affect gameplay however and did not add onto the duration of the weapon switching animation, so the reason for its speeding up is unknown.

If your view model is at its maximum, you can see a hand at the bottom while equipped with the Electro sapper.

In the " Meet the Spy" video the Spy is seen sliding the Sapper down on the floor to the Engineer's sentry. However, in the game, the Spy must be right up to the sentry in order to apply a sapper to an Engineer's sentry.

The Sapper is the only weapon that isn't a PDA (Personal Digital Assistant) that has infinite ammo. It also has no "cooldown" or "recharge" time, and is, to this day, the only weapon with no replacement. (As of December 17, 2010, the Demoman got a new Primary Weapon, the Loch-N-Load.)

When having the deadringer out and then switching to the sapper the spy appears to have a third arm that flicks the sappers switch